package org.example;

import com.mysql.cj.jdbc.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.*;
import java.text.MessageFormat;
import java.util.Scanner;

public class demo02_DataSource {
    public static void main(String[] args) {
        // 定义MySQL数据源对象
        MysqlDataSource mysqlDataSource = new MysqlDataSource();
        // 设置数据库连接串
        mysqlDataSource.setURL("jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf8" +
                "&allowPublicKeyRetrieval=true&useSSL=false");
        // 用户名
        mysqlDataSource.setUser("root");
        // 密码
        mysqlDataSource.setPassword("12345678");

        // 定义JDBC的数据源对象
        DataSource dataSource = mysqlDataSource;

        // 定义连接对象
        Connection connection = null;
        // 定义预处理SQL对象
        PreparedStatement statement = null;
        // 定义结果集对象
        ResultSet resultSet = null;

        try {
            // 1. 通过数据源获取数据库连接
            connection = dataSource.getConnection();
            // 2. 获取预处理SQL执行对象
            // 定义要执行的SQL
            String sql = "select student_id, sn,name,mail,class_id from student where name = ?";
            statement = connection.prepareStatement(sql);
            // 接收用户的输入
            System.out.println("请输入学生姓名:");
            Scanner scanner = new Scanner(System.in);
            String name = scanner.next();
            // 3. 用真实值替换占位符
            statement.setString(1,name);
            // 4. 执行SQL,获取结果集
            resultSet = statement.executeQuery();
            // 5. 遍历结果集
            while(resultSet.next()){
                // 获取学生ID
                long stuId = resultSet.getLong("student_id");
                String stuSn = resultSet.getString(2);
                String stuName = resultSet.getString(3);
                String mail = resultSet.getString(4);
                long classId = resultSet.getLong(5);
                System.out.println(MessageFormat.format("学生编号 = {0}, 学号 = {1},学生姓名 = {2}, " +
                                "学生邮箱 = {3}, 班级编号 = {4}",
                        stuId,stuSn, stuName,mail,classId));
            }

        } catch (SQLException e) {
            throw new RuntimeException(e);
        } finally {
            // 依次释放资源,关闭连接
            if (resultSet != null){
                try {
                    resultSet.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
            if (statement != null){
                try {
                    statement.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
            if(connection != null){
                try {
                    connection.close();
                } catch (SQLException e) {
                    throw new RuntimeException(e);
                }
            }
        }
    }
}
